A number of forms of lids and closures are known for covering the open end of a container and for selectively controlling the discharge of material from the container.
U.S. Pat. No. 3,028,993 to Muhlhoff shows a securing ring for locking a lid onto a container rim. The ring is locked into a securing position on the rim by a latch. The ring includes a plurality of retention flanges that overlap the rim of the container and engage the top and bottom sides of the rim and the edge of the lid.
U.S. Pat. No. 7,090,089 to Lown et al shows a combination container and sealing lid. The skirt portion of the lid includes a pair of rotatably mounted latches having protruding hooks thereon. Rotation of the latches into engagement with the rim of the container causes the hooks to secure the cover onto the rim.
U.S. Pat. No. 4,135,657 to Benson et al shows a locking ring assembly for a container. The ring is locked into a securing position on the rim by a latch. The ring includes an inwardly projected U-shaped channel that wraps around the outside of the rim of the container to secure the edge of the lid to the rim.
U.S. Ser. No. 2004/0256348 to Stevens et al shows an overcap or lid for a container having a circular hinged portion positioned between the rim engaging portion and the central planer portion. The rim engaging portion includes an inner skirt having a normal outside diameter that fits inside the wall of the container and an outer skirt that fits outside the container rim. Forcing the central planer portion of the lid downwardly into the container causes the circular hinged portion to flex and to push the skirt into a sealing engagement with the inside wall of the container.
U.S. Pat. No. 5,865,335 to Farrell et al shows in one embodiment a rim engaging ring having a removable tear strip portion that joins the peripheral skirt and the central wall of the lid. The tear strip is defined by two annular score lines in the wall of the lid.
U.S. Pat. No. 3,380,610 to Krieps shows a container lid having a peripheral skirt that fits over the rim of the container, sealing both to the inside and outside surfaces. Forcing a central portion of the lid downwardly, into the container, causes an extension flap on the central portion to flex or pivot into an inside sealing engagement with a groove formed on the inside wall of the container.
U.S. Pat. No. 5,979,690 to Hartley shows a peripheral skirt on a container rim having a tear-off strip formed between opposing engagement tabs. The tear-off strip initially extends downwardly from the upper rim engaging portion of the lid. The strip includes a locking groove that engages a locking lip formed on the outside surface of the container rim. When the strip is removed, the engagement tabs remain attached to the lid. The tabs can be flipped upwardly to release the lid from the rim of the container.